Oc has been alive for over 250 years and hasn't aged a day
Oc is over 250 years old.
He was a normal man, He was married and he had a daughter and a son.
But when years went by and he was 50 years old but didn't look a day over 30 he knew something was wrong.
He tried to use the excuse of a healthy diet, exercise and good genetics. But soon the suspicion caught up to him and he had to leave his family, faking his death.
More years go by and at 100 years old he still hasn't aged a bit.
He was constantly travelling and coming up with new identities. Never staying in one place more than 5 years. He has travelled all over the world.
He has learnt everything he could while trying to find an explanation for what had happened to him.
He had watched and attended the most historical events in all history. Fought in the wars.
He has met and became friends with historical figures. (Ex Elvis, Marilyn Monroe, etc)
He is extremely wealthy and has been able to keep his money by making his will out to a distant nephew (himself) faking his death and collecting the inheritance.
He has helped hundreds of business start up by investing in them.
2012 and the invasion happens and he accidentally runs into Steve (who he met in the war, faking his death in a Hydra attack) who last he knew was dead, they recognised each other instantly. But before Steve can say anything he runs away.
When Steve tells fury about it and how he didn't look a day over 30.
Fury gets his agents to search the footage. And after getting Tony's help they find pictures of the same man dating back hundreds of years all with different identities.
Fury sends Natasha to move into his apartment building and Seduce him.